Small to medium sized marine fishes. Body more or less compressed, perch-like (exclusive of Congrogadinae with eel-like body); mouth moderate to small, posterior end of jaws usually reaching or not to below middle of eye. Typically single dorsal fin, with I-III spines and 21-79 soft rays; anal fin with 0-III spines and 13-66 rays; pectoral fin with 16-20 soft rays; pelvic fin with I spine and 3-5 soft rays, except for several congrogadines lacking pelvic fin.